On Sat, 10 Apr 2021 08:53:50 -0400, bitrex <user@example.net> wrote:>On 4/10/2021 2:45 AM, upsidedown@downunder.com wrote: >> On Fri, 9 Apr 2021 16:41:54 -0400, bitrex <user@example.net> wrote: >> >>> On 4/9/2021 3:59 PM, Sid 03 wrote: >>>> On Friday, April 9, 2021 at 1:00:54 AM UTC-5, Jasen Betts wrote: >>>>> On 2021-04-09, Sid 03 <sidw...@gmail.com> wrote: >>>>>> How do I know if my surge suppressor is working ? I know it has a LED that stays lit as long as it is protecting, but does it really ? Is that light just there for amusement ? Most of the suppressors that I have seen just have a MOV soldered between the hot and neutral. If that's all these suppressors are, they why can't I open one up and just solder in some more MOVs and up the protection ? >>>>> In a MOV's usual wear-out mechanism they typically fail shorted. >>>>> When the MOV fails it blows a fuse and with the fuse blown the LED >>>>> goes out. >>>>> >>>>> It's possible (but rare) for the MOV to fail open (eg. one of the leads breaks due >>>>> to external vibrations), If that happens the fuse will not blow and >>>>> the LED will stay lit. >>>>> >>>>> -- >>>>> Jasen. >>>> >>>> Thanks for that info. >>>> So when purchasing, how does one tell a good Suppressor from a not good ? >>>> -or- all they all about the same ? (as long as the Joules are the same) >>>> Or can you just open it up and add as many MOVs as you feel needed ? >>>> >>>> Sid. >>> >>> The ones that offer a warranty/insurance policy on the equipment >>> connected to them up to X-thousand dollars might be good place to start >> >> Read carefully what that insurance policy actually require you to do, >> since you might need to upgrade your electric system, such as >> improving grounding or even add spark gaps at the mains entry :-). >> After this upgrade this add-on suppressor might not be needed at all. >> >> Those surge suppressor that are plugged in the socket protects only >> equipment (or extension cord) connected to it suppressor , but may >> fail miserably, if there are other connections e.g. to telephone, CATV >> or antenna systems or other devices connected to a different mains >> socket (even it has a same kind of suppressor). >> > >These are $19.99 at Amazon: > ><https://www.amazon.com/ESHLDTY-Protector-Weatherproof-Shockproof-Protection/dp/B08GSFXW77>Is those really legal in the US for outdoor use ? In Europe, at least IP44 would be needed for outdoor use.>And holy shit, look at this picture right here: > ><https://m.media-amazon.com/images/S/aplus-media/sc/e898d052-416b-40ba-80a4-e662ed83a6b9.__CR0,0,300,300_PT0_SX300_V1___.jpg>Apparently when inserting the ground pin of the plug will remove some isolation barrier from the line and neutral sockets, which may also protect these sockets against rain.>"ESHLDTY outdoor surge protector will effectively prevent the occurrence >of short-circuit or electric shock and other safety accidents caused by >water splash or light rain." > >There's no evidence this thing does what it claims. It has no GFCI. >There's no evidence it even well-protects the equipment connected! The >IP-X standards have nothing to do with protecting the _user_. Does >anyone believe it's really ETL certified? > >Here's Tripp-Lite's insurance policy: > ><https://www.tripplite.com/support/insurance-policy>Not very demanding requirements especially with phone line connected equipment, only requiring protectors from the same manufacturer on the phone line. To be really effective, the mains and phone line protectors must be _very_ close together (within 100 mm) so in practice in the same device that is plugged into a grounded mains socket.> >Someone said that price is a deciding factor, at my local brick-n-mortar >electronics supply shop 7 outlet Tripp-Lite power strips with the >guarantee up to $75,000 are the _same price_ as the above: > ><https://www.tripplite.com/protect-it-7-outlet-surge-protector-7-ft-cord-2160-joules-white-housing~SUPER7> > >Though it doesn't claim to be "waterproof" or show pictures of someone >sticking fuckin' tweezers in it, damn. > > > > >
SURGE SUPPRESSOR
Started by ●April 9, 2021
Reply by ●April 10, 20212021-04-10
Reply by ●April 10, 20212021-04-10
bitrex bullshitted: ==============> > These are $19.99 at Amazon: > > <https://www.amazon.com/ESHLDTY-Protector-Weatherproof-Shockproof-Protection/dp/B08GSFXW77> > > And holy shit, look at this picture right here: > > <https://m.media-amazon.com/images/S/aplus-media/sc/e898d052-416b-40ba-80a4-e662ed83a6b9.__CR0,0,300,300_PT0_SX300_V1___.jpg> >** Nothing wromg to see there.> "ESHLDTY outdoor surge protector will effectively prevent the occurrence > of short-circuit or electric shock and other safety accidents caused by > water splash or light rain." > > There's no evidence this thing does what it claims.** It make no actual claims other than ones about itself. 1. The thing is "splash proof" so will not short out or shock just because of light rain. 2. Only 3 pin plugs can be used with it and it has a current overload breaker like all such panels do. 3. The A and N pins are shuttered. 4. It has a MOV inside for good luck. ..... Phil
Reply by ●April 10, 20212021-04-10
On Sat, 10 Apr 2021 02:53:20 -0600, bud-- <null@void.com> wrote:> >Francois Martzloff was the surge expert at the US-NIST. He investigated >how much energy might be absorbed in a MOV in a plug in suppressor. >Branch circuits were 10M and longer, and the surge on incoming power >wires was up to 10,000A. (That is the maximum that has any reasonable >probability of occurring and is based on a 100,000A strike to a utility >pole adjacent to the house in typical urban overhead distribution. Only >5% of strikes are stronger.) The maximum energy at the MOV was a >surprisingly small 35 joules. In 13 of 15 cases it was 1 joule or less. > >There are 2 reasons the energy is so small. One is that at about 6,000V >there is arc-over from the service panel bussbars to the enclosure (this >appears to be a 'feature' of US panels). After the arc is established >the voltage is hundreds of volts. Since the enclosure/ground/neutral are >connected to the earthing system (US) that dumps most of the incoming >surge energy to earth.The professional method is to have proper spark gaps in the main distribution panel with known turn-on voltages. Better yet, have the spark gap outside the house. In countries with long mains lines, the customers at the end of the line is in the worst situation, since over voltages are largest. Think about an open transmission line, in which the forward wave is reflected back from the "open" end of the transmission line, increasing the voltage. Getting spark gaps at into the last pole of the long line would be the best solution. You could try to get the utility company to install such devices and even offer to pay for the installation.>The second reason is the impedance of the branch circuit wiring. A surge >is a very short event so current components are relatively high >frequency. The wire inductance is more important than the resistance and >the branch circuit impedance greatly limits the current to the MOVs, >which greatly limits the energy.With a "standard" 8/20 us lightning pulse the slew rate of 1 kA/us and 10 uH line inductance, the voltage drop is 1 kV, greatly simplifying the job for the MOV. In fact in large sites, a stepwise protection system is used, with spark gaps at mains entry, some lower voltage protection at intermediate panels and finally MOVs close to or in an equipment. These all rely on wiring inductance+resistance between each protection step There is no point of connecting MOVs directly in parallel with a spark gap, the MOV will be fried quite quickly.
Reply by ●April 11, 20212021-04-11
On 4/10/2021 4:09 PM, Phil Allison wrote:> bitrex bullshitted: > > ============== >> >> These are $19.99 at Amazon: >> >> <https://www.amazon.com/ESHLDTY-Protector-Weatherproof-Shockproof-Protection/dp/B08GSFXW77> >> >> And holy shit, look at this picture right here: >> >> <https://m.media-amazon.com/images/S/aplus-media/sc/e898d052-416b-40ba-80a4-e662ed83a6b9.__CR0,0,300,300_PT0_SX300_V1___.jpg> >> > > ** Nothing wromg to see there. > > >> "ESHLDTY outdoor surge protector will effectively prevent the occurrence >> of short-circuit or electric shock and other safety accidents caused by >> water splash or light rain." >> >> There's no evidence this thing does what it claims. > > ** It make no actual claims other than ones about itself. > > 1. The thing is "splash proof" so will not short out or shock just because of light rain. > > 2. Only 3 pin plugs can be used with it and it has a current overload breaker like all such panels do. > > 3. The A and N pins are shuttered. > > 4. It has a MOV inside for good luck. > > > > ..... Phil >The claims on this other one by the same manufacturer go a bit further: <https://www.amazon.com/ESHLDTY-Weatherproof-Protector-1500Joules-Waterproof/dp/B08PK9LS17> "IPX6 Waterproof and Shockproof" IP standards don't have anything to do with protecting the user AFAIK "Worry-free power for anywhere near water." Sort of like worry-free skydiving? IPX6 is more than a "water splash" it's high-pressure jets. I don't think they do this test with anything connected to it or powered up they're just looking for water intrusion in its "natural state" with all the shutters closed.
Reply by ●April 11, 20212021-04-11
On 4/11/2021 9:58 AM, bitrex wrote:> On 4/10/2021 4:09 PM, Phil Allison wrote: >> bitrex bullshitted: >> >> ============== >>> >>> These are $19.99 at Amazon: >>> >>> <https://www.amazon.com/ESHLDTY-Protector-Weatherproof-Shockproof-Protection/dp/B08GSFXW77> >>> >>> >>> And holy shit, look at this picture right here: >>> >>> <https://m.media-amazon.com/images/S/aplus-media/sc/e898d052-416b-40ba-80a4-e662ed83a6b9.__CR0,0,300,300_PT0_SX300_V1___.jpg> >>> >>> >> >> ** Nothing wromg to see there. >> >> >>> "ESHLDTY outdoor surge protector will effectively prevent the occurrence >>> of short-circuit or electric shock and other safety accidents caused by >>> water splash or light rain." >>> >>> There's no evidence this thing does what it claims. >> >> ** It make no actual claims other than ones about itself. >> >> 1. The thing is "splash proof" so will not short out or shock just >> because of light rain. >> >> 2. Only 3 pin plugs can be used with it and it has a current overload >> breaker like all such panels do. >> >> 3. The A and N pins are shuttered. >> >> 4. It has a MOV inside for good luck. >> >> >> >> ..... Phil >> > > The claims on this other one by the same manufacturer go a bit further: > > <https://www.amazon.com/ESHLDTY-Weatherproof-Protector-1500Joules-Waterproof/dp/B08PK9LS17> > > > "IPX6 Waterproof and Shockproof"Even strips with integrated GFCIs don't claim to be "shock-proof"
Reply by ●April 11, 20212021-04-11
On 4/10/2021 11:47 AM, upsidedown@downunder.com wrote:> On Sat, 10 Apr 2021 08:53:50 -0400, bitrex <user@example.net> wrote: > >> On 4/10/2021 2:45 AM, upsidedown@downunder.com wrote: >>> On Fri, 9 Apr 2021 16:41:54 -0400, bitrex <user@example.net> wrote: >>> >>>> On 4/9/2021 3:59 PM, Sid 03 wrote: >>>>> On Friday, April 9, 2021 at 1:00:54 AM UTC-5, Jasen Betts wrote: >>>>>> On 2021-04-09, Sid 03 <sidw...@gmail.com> wrote: >>>>>>> How do I know if my surge suppressor is working ? I know it has a LED that stays lit as long as it is protecting, but does it really ? Is that light just there for amusement ? Most of the suppressors that I have seen just have a MOV soldered between the hot and neutral. If that's all these suppressors are, they why can't I open one up and just solder in some more MOVs and up the protection ? >>>>>> In a MOV's usual wear-out mechanism they typically fail shorted. >>>>>> When the MOV fails it blows a fuse and with the fuse blown the LED >>>>>> goes out. >>>>>> >>>>>> It's possible (but rare) for the MOV to fail open (eg. one of the leads breaks due >>>>>> to external vibrations), If that happens the fuse will not blow and >>>>>> the LED will stay lit. >>>>>> >>>>>> -- >>>>>> Jasen. >>>>> >>>>> Thanks for that info. >>>>> So when purchasing, how does one tell a good Suppressor from a not good ? >>>>> -or- all they all about the same ? (as long as the Joules are the same) >>>>> Or can you just open it up and add as many MOVs as you feel needed ? >>>>> >>>>> Sid. >>>> >>>> The ones that offer a warranty/insurance policy on the equipment >>>> connected to them up to X-thousand dollars might be good place to start >>> >>> Read carefully what that insurance policy actually require you to do, >>> since you might need to upgrade your electric system, such as >>> improving grounding or even add spark gaps at the mains entry :-). >>> After this upgrade this add-on suppressor might not be needed at all. >>> >>> Those surge suppressor that are plugged in the socket protects only >>> equipment (or extension cord) connected to it suppressor , but may >>> fail miserably, if there are other connections e.g. to telephone, CATV >>> or antenna systems or other devices connected to a different mains >>> socket (even it has a same kind of suppressor). >>> >> >> These are $19.99 at Amazon: >> >> <https://www.amazon.com/ESHLDTY-Protector-Weatherproof-Shockproof-Protection/dp/B08GSFXW77> > > Is those really legal in the US for outdoor use ? In Europe, at least > IP44 would be needed for outdoor use.Beats me. Amazon don't care.>> And holy shit, look at this picture right here: >> >> <https://m.media-amazon.com/images/S/aplus-media/sc/e898d052-416b-40ba-80a4-e662ed83a6b9.__CR0,0,300,300_PT0_SX300_V1___.jpg> > > Apparently when inserting the ground pin of the plug will remove some > isolation barrier from the line and neutral sockets, which may also > protect these sockets against rain.This other one advertises "shock proof": <https://www.amazon.com/ESHLDTY-Weatherproof-Protector-1500Joules-Waterproof/dp/B08PK9LS17> A surge protector that also offered integrated GFCI would be nice but they seem hard to come by as these are somewhat contradictory goals. Maybe putting the surge protecting device upstream of the GFCI would work in some cases.
Reply by ●April 11, 20212021-04-11
On 4/10/2021 5:04 PM, upsidedown@downunder.com wrote:> On Sat, 10 Apr 2021 02:53:20 -0600, bud-- <null@void.com> wrote: > >> >> Francois Martzloff was the surge expert at the US-NIST. He investigated >> how much energy might be absorbed in a MOV in a plug in suppressor. >> Branch circuits were 10M and longer, and the surge on incoming power >> wires was up to 10,000A. (That is the maximum that has any reasonable >> probability of occurring and is based on a 100,000A strike to a utility >> pole adjacent to the house in typical urban overhead distribution. Only >> 5% of strikes are stronger.) The maximum energy at the MOV was a >> surprisingly small 35 joules. In 13 of 15 cases it was 1 joule or less. >> >> There are 2 reasons the energy is so small. One is that at about 6,000V >> there is arc-over from the service panel bussbars to the enclosure (this >> appears to be a 'feature' of US panels). After the arc is established >> the voltage is hundreds of volts. Since the enclosure/ground/neutral are >> connected to the earthing system (US) that dumps most of the incoming >> surge energy to earth. > > The professional method is to have proper spark gaps in the main > distribution panel with known turn-on voltages. Better yet, have the > spark gap outside the house. > > In countries with long mains lines, the customers at the end of the > line is in the worst situation, since over voltages are largest. Think > about an open transmission line, in which the forward wave is > reflected back from the "open" end of the transmission line, > increasing the voltage. Getting spark gaps at into the last pole of > the long line would be the best solution. You could try to get the > utility company to install such devices and even offer to pay for the > installation.Yes, over distances like a hundred miles the electrical length of the line at 50-60Hz is enough to cause reflection-effects like with RF in an unterminated cable and give a nice boost at the end, there's an analysis in e.g.: <https://www.worldcat.org/title/transmission-lines-and-networks/oclc/600926364>>> The second reason is the impedance of the branch circuit wiring. A surge >> is a very short event so current components are relatively high >> frequency. The wire inductance is more important than the resistance and >> the branch circuit impedance greatly limits the current to the MOVs, >> which greatly limits the energy. > > With a "standard" 8/20 us lightning pulse the slew rate of 1 kA/us and > 10 uH line inductance, the voltage drop is 1 kV, greatly simplifying > the job for the MOV. In fact in large sites, a stepwise protection > system is used, with spark gaps at mains entry, some lower voltage > protection at intermediate panels and finally MOVs close to or in an > equipment. These all rely on wiring inductance+resistance between each > protection step There is no point of connecting MOVs directly in > parallel with a spark gap, the MOV will be fried quite quickly. >
Reply by ●April 11, 20212021-04-11
On 4/10/2021 3:04 PM, upsidedown@downunder.com wrote:> On Sat, 10 Apr 2021 02:53:20 -0600, bud-- <null@void.com> wrote: > >> >> Francois Martzloff was the surge expert at the US-NIST. He investigated >> how much energy might be absorbed in a MOV in a plug in suppressor. >> Branch circuits were 10M and longer, and the surge on incoming power >> wires was up to 10,000A. (That is the maximum that has any reasonable >> probability of occurring and is based on a 100,000A strike to a utility >> pole adjacent to the house in typical urban overhead distribution. Only >> 5% of strikes are stronger.) The maximum energy at the MOV was a >> surprisingly small 35 joules. In 13 of 15 cases it was 1 joule or less. >> >> There are 2 reasons the energy is so small. One is that at about 6,000V >> there is arc-over from the service panel bussbars to the enclosure (this >> appears to be a 'feature' of US panels). After the arc is established >> the voltage is hundreds of volts. Since the enclosure/ground/neutral are >> connected to the earthing system (US) that dumps most of the incoming >> surge energy to earth. > > The professional method is to have proper spark gaps in the main > distribution panel with known turn-on voltages. Better yet, have the > spark gap outside the house. > > In countries with long mains lines, the customers at the end of the > line is in the worst situation, since over voltages are largest. Think > about an open transmission line, in which the forward wave is > reflected back from the "open" end of the transmission line, > increasing the voltage. Getting spark gaps at into the last pole of > the long line would be the best solution. You could try to get the > utility company to install such devices and even offer to pay for the > installation. >I have never heard of or seen spark gaps in, or added to, panelboards here (US) other than what appears to be an intentional design to arc-over. A short duration 10kA max surge is well within the capabilities of MOV based protection. Also don't know of spark gaps in bigger commercial/industrial service switchgear.I have seen MOV based protection. The max surge should still be something like 10kA (less because of 4 wire 3-phase, more because transformers only supply one building). It is common to have a lightning arrester across the primary (distribution side) of pole mounted transformers. They needed to be there to protect the transformer. Rural overhead distribution lines have lightning arresters. I saw a stretch that had an arrester on every other pole. A line-to-earth arrester will drastically lift the ground potential at that pole (crappy earth electrode). I think the analysis by Martzloff that found a maximum probable 10kA surge per service wire had a strike to the primary wire and an arrester across the primary of the supply transformer. The surge was (H-N-H) to earth at the transformer (surge current lifted 'ground' at the transformer, as above). Earthing the N at the service results in H-N surge. Arresters may not be a simple gap - that can result in "follow-on" arc from normal power immediately following an event. Don't know if "mains lines" refers to primary side, secondary side or both.>> The second reason is the impedance of the branch circuit wiring. A surge >> is a very short event so current components are relatively high >> frequency. The wire inductance is more important than the resistance and >> the branch circuit impedance greatly limits the current to the MOVs, >> which greatly limits the energy. > > With a "standard" 8/20 us lightning pulse the slew rate of 1 kA/us and > 10 uH line inductance, the voltage drop is 1 kV, greatly simplifying > the job for the MOV. In fact in large sites, a stepwise protection > system is used, with spark gaps at mains entry, some lower voltage > protection at intermediate panels and finally MOVs close to or in an > equipment. These all rely on wiring inductance+resistance between each > protection step There is no point of connecting MOVs directly in > parallel with a spark gap, the MOV will be fried quite quickly. >
Reply by ●April 11, 20212021-04-11
On Fri, 09 Apr 2021 15:14:11 -0700, John Larkin <jlarkin@highland_atwork_technology.com> wrote:>On Thu, 8 Apr 2021 22:14:05 -0700 (PDT), Sid 03 <sidwelle@gmail.com> >wrote: > >>How do I know if my surge suppressor is working ? I know it has a LED that stays lit as long as it is protecting, but does it really ? Is that light just there for amusement ? Most of the suppressors that I have seen just have a MOV soldered between the hot and neutral. If that's all these suppressors are, they why can't I open one up and just solder in some more MOVs and up the protection ? >> >>Thanks >>Sid. > >Why bother?Maybe it's of unknown provenance. I came across some cheap Chinese multiple adaptors for 240V use (as they claimed anyway) and none of the earths were connected to anything, despite having 3 pin sockets for live neutral and earth. And they came from a well known DIY chain in the UK too. Natch I reported it and they got withdrawn/recalled.
Reply by ●April 11, 20212021-04-11
On Sun, 11 Apr 2021 10:56:17 -0400, bitrex <user@example.net> wrote:>On 4/10/2021 5:04 PM, upsidedown@downunder.com wrote: >> On Sat, 10 Apr 2021 02:53:20 -0600, bud-- <null@void.com> wrote: >> >>> >>> Francois Martzloff was the surge expert at the US-NIST. He investigated >>> how much energy might be absorbed in a MOV in a plug in suppressor. >>> Branch circuits were 10M and longer, and the surge on incoming power >>> wires was up to 10,000A. (That is the maximum that has any reasonable >>> probability of occurring and is based on a 100,000A strike to a utility >>> pole adjacent to the house in typical urban overhead distribution. Only >>> 5% of strikes are stronger.) The maximum energy at the MOV was a >>> surprisingly small 35 joules. In 13 of 15 cases it was 1 joule or less. >>> >>> There are 2 reasons the energy is so small. One is that at about 6,000V >>> there is arc-over from the service panel bussbars to the enclosure (this >>> appears to be a 'feature' of US panels). After the arc is established >>> the voltage is hundreds of volts. Since the enclosure/ground/neutral are >>> connected to the earthing system (US) that dumps most of the incoming >>> surge energy to earth. >> >> The professional method is to have proper spark gaps in the main >> distribution panel with known turn-on voltages. Better yet, have the >> spark gap outside the house. >> >> In countries with long mains lines, the customers at the end of the >> line is in the worst situation, since over voltages are largest. Think >> about an open transmission line, in which the forward wave is >> reflected back from the "open" end of the transmission line, >> increasing the voltage. Getting spark gaps at into the last pole of >> the long line would be the best solution. You could try to get the >> utility company to install such devices and even offer to pay for the >> installation. > >Yes, over distances like a hundred miles the electrical length of the >line at 50-60Hz is enough to cause reflection-effects like with RF in an >unterminated cable and give a nice boost at the end, there's an analysis >in e.g.: > ><https://www.worldcat.org/title/transmission-lines-and-networks/oclc/600926364>Lightnings are RF. Just listen with a radio at LF/MF bands and even up to lower part of the HF band and you can hear crackle all over, especially in the summer. While the "standard" lightning current pulse is 8/20 us, some sources claim a 3 ,s rise time, i.e. 10 us cycle time or 100 kHz frequency. This translates to a 3 km wavelength. In the 230/400 V world low voltage distribution lines can be longer than a kilometer, which is a significant part of the wavelength and transmission line issues must be observed. Since the power line RF impedance is a few hundred ohms and one or both ends of the transmission line has an open circuit., the RF pulse will reflect a few times back and forth, until attenuated by resistive losses or flashovers.
